Crackership

Hi all,

I just read through several similar threads, but I don't seem to find my precise symptoms. So, I figure I'll start my own.

Two days ago, I was warming my car up after work, just like I always do, and the idle began to surge. It's clearly the ISV surging it. It seemed to coincide with the car warming up just enough to enter closed loop. I gave it a touch of gas and it smoothed out, so I drove it home without event.

Yesterday, while warming it up to go to work, the idle started surging again. Gave it some gas and it smoothed out, but the whole drive into work was really rich. Around 13 at idle, low 12's while cruising and into the 9's under boost.

After work, I had a very similar warm-up and drive home, but, by the time I got home, it was surging badly at idle all the time and giving it gas didn't smooth it out.

Spent a few hours last night chasing vacuum leaks, found a few, fixed them, and started her up.. as soon as she warmed up, surging idle again. I thought I'd give adjusting the idle a shot, just to see what happened, and it smoothed out just fine once I got it up to just under 1k. As soon as it smoothed out, it started to idle at reasonable AFRs, so I went for a quick drive. Everything seemed fine and AFRs were good.

This morning, I fired it up, and it immediately started surging. So, now the issue presents when cold? I adjusted the idle again and took it up to about 1100 before it smoothed out. I had to get to work, so I just jumped in and drove. Now, AFRs are a little rich at idle, but not bad - 14.5ish, but now it's in the mid 12's while cruising and I hit low 10's pulling away from a light off of boost.

Totally baffled. Any ideas?

TIA!

Crazy Eddie

Probably a long shot but...
If you have access to a spare known working KLR
I would just see if that is the issue ,....
After searching high and low that's what it turned out to be ..
It's just an easy thing to try...
Mine had similar symptoms and it was the KLR solder joints....
Good luck
regards
Ed

Crackership

Thanks Ed! I read your thread about it, and I'm hoping a buddy of mine has a KLR I can try. If I can get ahold of one, it's a pretty easy test.

Crackership

I messed with it all day yesterday... Checked all sorts of things... Completely ran out of ideas...

Then, I figured that I'd install the new LR speed and reference sensor harness I've had sitting on the shelf for a while... Not really because I thought it might fix the problem, but just because I was out of ideas and I wanted to do something straight-forward for a moment instead of chase a ghost.

That solved the problem. I'm not sure I understand how, but it did.

I shot this video of the way it idled before I swapped the harness, I suppose I'll put it up, just so the next guy with a weird surging idle problem can see if they've got the same issue.

I'm not touching the throttle at any point during this video, and AFR's are all over the place the whole time it surging. Towards the end, when it smooths out, AFR's are in the low 13's

Crackership

I don't know why the video is showing up twice in the above post.. They're the same video, and I embedded it only once.. No idea.

gruhsy

glad to hear you got it fixed.

Crazy Eddie

Mine did sound a little like that, but was even more dramatic, in the first minute of the start up
Then once it warmed, it would settle down and then it would run rich at 13.5
What is that banging noise I hear in the background ?
Post a video of it running now ...
I hope that's it ...
Regards
Ed

Rogue_Ant

[Y T]o2Jly9m1q9M[/Y T]

Remove the space between Y T.

kent426

Hey there, another Washingtonian. I am in seattle. I am having a similar issue with my car, I found boosts leaks that was causing an issue, I adjusted idle and that smoothed things out but I know there is also an mixture adjustment that can be performed. I have a nasty exhaust smell in the interior that I am trying to trouble shoot too.
Have you tried Fordahl or Group 2 motorsports? I was going to drop my car off at Fordahl to have them tune it.

Kent

Ronin-951

Hey Crackership, wonder how the DME Temp Sensor connections looked? Any 'cold' Engine Rich/Lean issues and that's a good bet, 'warm' Engine Rich/Lean would include a O2 sensor check. Cold AND Warm surging would get an ISV inspection too.